1. Field of the Invention
The present invention relates to a thermoplastic elastomer composition having excellent steam permeation resistance and heat distortion resistance, insulating glass using the composition as a sealing material and spacer, a process for producing the insulating glass and a nozzle for producing the insulating glass.
2. Prior Art
Heretofore, there has been known insulating glass constituted such that a sealing material having a predetermined width is charged into a space between the peripheral portions of at least two glass sheets which are opposed to each other in parallel and the hollow layer between the glass sheets is isolated from the outside air for the purpose of an improvement of heat insulating properties, dew condensation prevention properties and the like.
This insulating glass has been produced as follows, for example. As shown in FIG. 7, an aluminum spacer 73 filled with a desiccating agent 72 is placed in a space between the peripheral portions of two glass sheets 71a and 71b which are opposed to each other in parallel and held by a jig or the like to fix a predetermined interval between the glass sheets. Thereafter, a primary sealing material 74 is charged into spaces between the both side surfaces of the spacer 73 and the glass sheets 71a and 71b, and a two-liquid mixing and normal temperature curable type secondary sealing material 75, for example by a polysulfide- or silicone-based sealing material, is charged into a space between the spacer 73 and the opening side of the glass sheets 71 and 71b. 
Japanese Patent Application Laid-Open No. Hei 10-158041 discloses a insulating glass production process and apparatus. In the process and apparatus, a plurality of glass sheets are held in a perpendicular direction so that the plurality of glass sheets can be simultaneously moved in the same direction at the same speed, the glass sheets and a die are moved in different unidirections which are perpendicular to each other, the glass sheets and the die are moved relative to each other alternately such that the glass sheets are stopped when the die is moved, and vice versa, and a resin material is extruded onto the peripheral portions of the glass sheets opposed to each other by moving the glass sheets and the die alternately for each side of the glass sheets.
However, since the former production process is carried out by using a jig, spacer and the like, the work becomes complicated and takes much time and labor. On the other hand, the latter process has such a problem that it is difficult to obtain insulating glass having good appearance because the resin material cannot be paved nicely when it is extruded.
In the insulating glass using the normal temperature curable sealing material in the prior art processes, it takes time to cure the sealing material and a final product cannot be promptly shipped. Especially in winter, the sealing material must be placed in a heating chamber for curing.
Therefore, it is desired to improve productivity by simplifying the process for producing insulating glass and shortening the cure time.
In contrast to this, Japanese Patent Application Laid-Open Nos. Hei 10-110072, Hei 10-114551, Hei 10-114552 and the like propose an invention in which a resin containing a desiccating agent as required is used as a spacer and sealing material in place of the aluminum spacer. The spacer/sealing material proposed in these publications is a composition containing butyl-based rubber and crystalline polyolefin which are preferably mixed at a high temperature.
In insulating glass using this composition, the composition serves as a resin spacer and a sealing material. Insulating glass can be produced in which the peripheral portions of the glass sheets are sealed up by paving the composition on the peripheral portions of two glass sheets opposed to each other with a spacer therebetween. Thus, the production process is simplified. However, in this insulating glass, the glass sheets are not dislocated each other when a load is placed upon the glass sheets at normal temperature but the glass sheets are dislocated each other while a high-temperature sealing material is paved and cured especially when the insulating glass is produced or when the temperature of the outside air rises in summer or by sunlight after the insulating glass is formed into a construction material or the like because the composition which serves as a sealing material and resin spacer contains a small amount of a resin in rubber and hence, is easily deformed at high temperatures.
It is a first object of the present invention to provide a thermoplastic elastomer composition which has excellent steam permeation resistance and heat distortion resistance and is suitable for use as a sealing material and spacer for insulating glass.
It is a second object of the present invention to provide insulating glass which uses the thermoplastic elastomer composition as a sealingmaterial and spacer, is produced easily, has excellent steam permeation resistance and is not deformed in the entire shape by the dislocation of the glass sheets when it is allowed to cool after the sealing material and spacer is paved, or after processing or at high temperatures in summer or the like.
It is a third object of the present invention to provide a process for producing insulatingglass which enables a sealing material to be efficiently paved in a space between the peripheral portions of glass sheets and leveled to obtain good appearance and reduces the number of working steps to carry out efficient work.
It is a fourth object of the present invention to provide a nozzle for producing insulating glass which can be advantageously used in the above process for producing insulating glass.
The inventor of the present invention has conducted intensive studies to solve the above problems and have found that the above objects can be attained by a thermoplastic elastomer composition containing a continuous phase formed of a thermoplastic resin having a water vapor permeability below a predetermined value and a dispersion phase formed by dynamically crosslinking a rubber component having a water vapor permeability below a predetermined value after crosslinking, and insulating glass using the composition as a sealing material and spacer. Thus, the present invention has been accomplished based on this finding.
To attain the first object, the present invention provides a thermoplastic elastomer composition which is produced from a thermoplastic resin having a water vapor permeability of 100 g/m2xc2x724 h or less (30 xcexcm in thickness) and rubber having a water vapor permeability of 300 g/m2xc2x724 or less (30 xcexcm in thickness) when crosslinked and which has a dispersion phase formed of a rubber composition at least part of which is dynamically crosslinked in the continuous phase of the thermoplastic resin.
To attain the second object, the present invention provides insulating glass which uses the thermoplastic elastomer composition as a sealing material and spacer.
To attain the third object, the present invention provides a process for producing insulating glass by charging a sealing material having a predetermined width into a space between the peripheral portions of at least two glass sheets which are opposed to each other in parallel at a predetermined interval to isolate the hollow layer from the outside air, the process comprising the steps of inserting in advance the leading end of a charging nozzle into a space between the peripheral portions of a plurality of glass sheets, contacting a slide plate provided at the top of the leading end portion of the nozzle to the peripheral portions of the plurality of glass sheets, discharging a sealing material from the leading end of the nozzle body at a predetermined rate, and moving at least one of the glass sheets and the nozzle body relative to the other to charge the sealing material from the leading end portion of the nozzle into the space between the peripheral portions of the glass sheets.
To attain the fourth object, the present invention provides a nozzle for producing insulating glass by inserting the leading end portion of the nozzle into a space between the peripheral portions of at least two glass sheets which are opposed to each other in parallel at a predetermined interval, and charging a sealing material from the leading end portion of the nozzle into the space between the peripheral portions of the glass sheets while at least one of the glass sheets and the nozzle body is moved relative to the other, wherein the leading end of the nozzle body has a width for positioning the interval between the plurality of glass sheets, and a slide plate which slides along the peripheral portions of the plurality of glass sheets and is provided at the top of the leading end portion.